1. Field of the Invention
This invention relates to automotive signal devices, and more particularly relates to a deceleration expectation warning controller and associated signal lights for signaling various levels of stopping expectation, from temporary slowdown due to a tap on the brake, or slowdown from coasting through ordinary stopping, to standard stopping, to panic stopping.
2. Description of the Related Art
Brakelight signals to indicate a stopping operation have been included in automobiles almost since the advent of electric lighting. A signal control switch activated by depression of the brake pedal (later by sensing the buildup of hydraulic pressure, or air pressure, in the braking system) controlled a bright taillight (later two or three taillights) to turn on a set of stop-warning taillights, or cause the existing lighted running taillight set to glow more brightly.
Next came hazard warning flashers, which, as popularly deployed, signal by flashing the full set of taillights (or special hazard warning lights) as if both a right turn and a left turn were simultaneously to be expected, and thus to signal a hazard ahead.
One other set of rear lights appears on most modern vehicles--backup lights. Automatic from the placement of the gearshift lever into reverse, such lights not only provide light to see by, but also provide an indication of expectation to reverse. Most large trucks supplement or supplant the backup light by a backup warning gong.
Turn signals have been popularly mounted on automobiles and trucks since the late-thirties Buick popularized the practice of manually selecting a signal of an intent to turn, which activated an arrow light, and later activated such things as the pop-up semaphore on the early VW and the current blinking turn signal of red or yellow light. The turn signal not only signals an intent to turn--but also gives the important information of WHAT TO EXPECT (right turn? or left turn?).
An automotive aftermarket device, sold mostly as a novelty item, was a miniature traffic signal light for mounting in the rear window of a car. Red, yellow and green lights in the miniature traffic signal were connected in a simple pattern in which the red light mimicked the brake warning signal lights and the green and yellow lights glowed in parallel with the headlights.
Prior to this invention, however, there has been no additional information (EXPECTATION INFORMATION) added to the intent-to-stop information passed by the brakelight. The first following motorist may be dangerously misled by a brakelight signal resulting from a light touch on the brake, sufficient to activate the brakelight by insufficient to accomplish any significant deceleration. To the first following motorist, that brakelight may be interpreted as a command to stop! The EXPECTATION INFORMATION is reasonable, but faulty! If the first following motorist reacts by a panicstop, that panicstop may trigger a multiple rear-end collision! If the second following and subsequent following motorists cannot stop in time--even though in fact there never was need for the first following motorist to stop--they may crash in turn into the rear of the respectively preceding vehicles.
The problem is that the binary (off/on) brakelight signal in fact is ambiguous. This ambiguous brakelight warns of a stop, regardless of whether the expectation is an actual stop (a panicstop or a gentle stop) or simply a slowdown, or even a light, continuing touch by the preceding car driver's foot lightly resting on the brake pedal.